This invention relates to a rim disc adjustable to different sized rims, particularly to one provided with a plurality of engagement members spaced apart around an outer circumferential edge for a steel ring to engage with all the engagement members to enable the rim disc to be adjustable to different sized rims by means of one of the engagement members provided with a few engagement grooves for the steel ring to selectively fit in one of the engagement grooves.
Conventional rims have different sizes according to the types of cars, and the rim discs have a single size to suit to only one kind of car, which are impossible to be used in different sized rims. If the rim is comparatively small, a rim disc may not be easily assembled with the rim. On the contrary, if the rim is comparatively large, a rim disc may be assembled with the rim, but hardly contact tightly the inner wall of the rim, and be liable to become loose, and fall off if worse.